Repotting guide

When & how to repot Arum italicum (Arum italicum)

Also called Italian Arum, Italian Lords-and-Ladies.

More about arum italicum

About Arum italicum

Arum italicum · also called Italian Arum, Italian Lords-and-Ladies · houseplant

Arum italicum is a hardy tuberous aroid grown for its arrow-shaped, cream-veined leaves that emerge in autumn and persist through winter. A pale spring spathe is followed by a striking spike of orange-red berries after the foliage dies back. It thrives in shade and is widely grown as a winter-interest woodland and container plant.

Mature size: Reaches about 30-45 cm tall and 30 cm wide; can naturalise into broad colonies over time.

How to tell arum italicum needs repotting

Repotting on a calendar is less reliable than reading the plant. For arum italicum, watch for these signs:

Flowering has tailed off year on year and the clump has become congested and overcrowded.
Lots of leaf and few flowers — a classic sign that arum italicum bulbs or tubers need lifting and dividing.
Bulbs visibly bursting the pot or pushing each other to the surface.
It is the natural dormancy window (foliage yellowed and died back) — the only safe time to lift and split.

For the underlying biology of a pot-bound root system and why it stalls a plant, see our guide to spotting and fixing a root-bound plant.

How often to repot arum italicum

Lift and divide every 3–4 years once clumps congest. Rather than a true repot, arum italicum is lifted and divided once the clump congests and flowering drops off. Clump-forming, tuberous herbaceous perennial with a reverse seasonal cycle: leaves appear in autumn, die back in early summer, and a spike of orange-red berries follows. Spreads steadily by tubers and self-seeding berries..

What size pot to step arum italicum up to

Pot size matters less than depth and spacing here. When you replant arum italicum, set the bulbs or tubers at the correct depth (a rough guide: two to three times their own height of soil over the top) and space them so they are not touching. A wide, shallow pot suits a clump better than a tall narrow one.

Not sure of the exact diameter? Our pot size calculator takes the current pot and root spread and tells you the right next size — it deliberately recommends a single step up, never a big jump.

The best time of year to repot arum italicum

The only safe window is dormancy: wait until the foliage has yellowed and died back naturally, lift and divide then, and replant before or at the start of the next growing season. Disturbing arum italicum in full growth or flower sets it back badly.

Step-by-step: repotting arum italicum

Wait for dormancy. Let arum italicum foliage yellow and die back completely. Lifting while it is in growth wastes the energy it is storing for next year.
Lift carefully. Loosen the soil well away from the bulbs/tubers with a fork and ease the whole clump out without spearing them.
Separate the offsets. Gently pull the clump apart into individual bulbs or tubers. Keep only firm, healthy, blemish-free ones.
Replant at the right depth. Reset them in fresh humus-rich, free-draining soil at the correct depth and spacing — not touching — so each has room to bulk up.
Water in and rest. Water once to settle them, then keep on the dry side until growth resumes. Do not feed until leaves are actively growing.

Aftercare

After replanting arum italicum, keep the soil barely moist — not wet — until shoots appear; bulbs and tubers rot in cold, saturated soil. Once leaves are growing strongly, resume normal watering. Hold off feeding until the plant is in active growth again.

The right soil mix for arum italicum

Arum italicum wants humus-rich, free-draining soil. Grows best in moist but well-drained, fertile soil enriched with leaf mould or compost. Heavy, waterlogged ground rots the tubers; a woodland-style soil with good organic matter is ideal. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting arum italicum — frequently asked questions

How often should you repot arum italicum?

Lift and divide every 3–4 years once clumps congest for arum italicum. Arum italicum is lifted and divided, not "repotted". Every 3–4 years, once the foliage has died back and it is dormant, lift the clump, separate the offsets, and replant at the correct depth in humus-rich, free-draining soil. Crowding, not pot size, is what reduces flowering over time.

What size pot does arum italicum need?

When is the best time of year to repot arum italicum?

Do you "repot" arum italicum, or lift and divide it?

You lift and divide it. Arum italicum grows from bulbs or tubers, so instead of repotting you wait for dormancy, lift the congested clump, separate the healthy offsets, and replant them at the right depth and spacing. Doing this every 3–4 years restores flowering.

Should you fertilise arum italicum after repotting?

Hold off feeding arum italicum until it is in active growth again. Fresh soil already carries enough nutrients to get it re-established, and feeding disturbed roots too soon does more harm than good.